钢带梁锚杆支护在马兰矿2号煤层回采巷道的应用

介绍马兰矿2号煤层回采巷道支护参数的确定、支护技术要求、技术经济效果和存在问题及改进措施。

掘进巷道过大断层区支护技术

基于阜生煤矿1306运输顺槽掘进过DF7大断层期间围岩出现严重失稳现象,造成顶板支护难度大、破断率高、巷道掘进速度慢等问题,通过技术研究,对原顶板锚杆(索)支护进行合理优化,提出了“桁架锚索+梯形梁钢带+π型钢棚”联合支护技术。通过实际应用效果来看,大断层区支护优化后控制断层牵引导致围岩破碎、下沉现象,锚杆(索)失效率由原来的13%降低为4%,巷道过断层区掘进速度提高至4.8 m/d,取得了显著应用成效。

石壕矿13261工作面沿空掘巷实践

石壕煤矿在下部13281工作面正在生产的情况下,设计采用沿空掘巷施工相邻的13261工作面运输巷。通过对巷道围岩抗压特点的分析,针对性地选取了主动强力支护和松帮让压支护工艺相结合的支护设计,并在13281回风巷进行爆破切顶,减少顶板对13261运输巷的应力作用。实践表明,采用沿空掘巷使13261工作面运输巷经受住了动压的反复影响,减少了修巷工作量,取得了较好效果。

Nonlinear Behavior of Reinforced Concrete Slit Shear Walls under Seismic Actions *

A reinforced concrete slit shear wall is a new breed of earthquake resistant structure recently proposed by the authors. In this paper, the seismic responses of the slit shear walls under the shake of earthquake excitation have been dealt with. Based on a simplified structural model, which is shown to have a sufficient accuracy for the real slit shear wall structure, the analysis focuses on the influence of nonlinear behavior of the connecting beams between the slits on the dynamic performance of the whole slit shear wall structure. It has been found that the yielding of connecting beams in a slit shear wall can provide significant improvement in reducing the structural responses, and by choosing an appropriate strength value for the connecting beams, it is possible to optimize the seismic response of the slit shear wall.

大断面切眼支护技术实践

针对耿村煤矿12170工作面的地质条件及开采技术,提出了大断面综放切眼支护采用锚网索加钢带梁耦合支护配合单体柱的联合支护方式;通过对支护参数的合理选取,同时对巷道离层和锚杆受力的检测,有效地控制了大断面切眼顶板及两帮的变形问题。

综采工作面沿空留巷支护技术

为了提高煤炭回采率并实现煤矿可持续发展,以长城五矿为背景,对沿空留巷支护技术进行了分析,并对留巷段矿压进行了观测。观测结果表明,随着1301N采煤工作面的接近和远离,沿空留巷段围岩变形会经历稳定→强烈活动→再稳定的过程,沿空留巷技术实现了无煤柱开采,提高了资源回采率、降低了巷道掘进率、改善了矿井接续条件,是具有发展前景的一项采煤技术。此研究对于今后推广该技术、保持煤炭事业健康发展有重要意义。